Airplane



C. H. CONGDON AIRPLANE Filed Nov. 15, 1925 I Juuculot Ch. CON$ Nov. 10, '1931.

Patented Nov. 10, 1931 UNITED STATES GLEM H. CONGDON, OF DOYLESTOWN, PENNSYLVANIA AIRPLANE Application filed November 15, 1923. Serial No. 874,995.

This invention relates to improvements in airplanes and more particularly to the construction of airplane wings whereby the lateral control of airplanes at low speeds and hi h angles of attack may be increased.

%)ne of the objects of the present invention is to provide a simple and practical mechanism of the abox e general character which may be inexpensively manufactured, assembled and installed.

A further object is to provide a flat mechanism for airplane wings adapted to spoil the lift and increase the drag on the up aileron side of the machine and thereby increase the lateral control of the machine at low speeds and high angles of attack.

Other objects will be in part obvious and in part hereinafter pointed out in connection with the accompanying sheet of drawings.

Figure 1 is a transverse, partial, sectional and diagrammatic view showing the invention as applied to an airplane wing in full line position and in dotted line position when operated.

Figure 2 is a plan View of a portion of the wing.

Referring now to the drawings in detail, 5 denotes the lower surface of an airplane wing of standard construction and 6 the upper surface extending between two beams 7 positioned longitudinally of the wing and at the rear there is provided the usual hinged aileron 8 hinged to the rear beam 7 at the point 10 whereby it may be swung upwardly or down wardly as indicated by the dotted line position. Along the forward edge of the wing is mounted the nose flap 11 normally occupying a position in a longitudinal recess whereby its upper surface is flush with and conforms to the upper surface of the wing.

This flap is hinged at the point 12 as provided with a pivotally connected link 13, one end of which is connected with a second pivot link 14 secured by a pivot 15 to a suitable bracket 16, the links 13 and 14 together forming a togglenormally held in restricted position by means of spring 17 Extending rearwardly of the machine is a link 18, the rear end of which is pivoted at 20 to an aileron horn 21 in such a manner that as the toggle 13-14 is moved to extended position the nose flap 11 will be moved upwardly as shown by its dotted line position and simultaneously the aileron will also be moved. There is, however, a certain amount of lost motion and definite ratio of movement whereby the aileron may be moved a certain extent without moving the nose flap. Perhaps this can be better explained by a brief Ttatement of the operation which is as folows.

As above stated the operating mechanism for the nose flap 11 acts, in the specific instance shown, against the resistance of spring 17 connected to the toggle links and push rod 18 which extends rearwardly to the aileron horn. The relation between the horn and the push rod or link 18 is such that when the aileron is 5 above normal, or the first dotted line position shown in Figure '1, the horn will come in contact with. the push rod and any further movement of the aileron towards the 30 or up er dotted line position will force the nose ap up proportionately. Ratio of the linkage is such that movement of the aileron from the 5 position to the 30 position downwardly from the full line position shown in Fig. 1, will produce substantially no movement of the nose fia therefore, it will be seen that the nose ap only comes into 0 eration when the aileron moves upwardly a ove the 5 position and does not function when the aileron moves downwardly and consequently the contour of the win will not be broken and'there will be 35 no isturbance of the air flow thereover. In other words, the flap mechanism is designed to spoil the lift and increase the drag on the up aileron side of the machine and consequently increase the lateral control of the machine at slow speeds and high angles of attack.

It will thus be seen that the presentinvention provides a reliable and efficient mechanism adapted to accomplish, among others, all of the objects and advantages herein set forth.

Without further analysis, the foregoing will so fully reveal the gist of this invention that others can by applying current kn0wl-- edge readily adapt it for various ap lications without omitting certain features t at, from the standpoint of the prior art, fairlyconstitute essential characteristics of the generic or specific aspects of this invention, and, therefore, such adaptations should and are intended to be com rehended within the meaning and range 0 equivalency of the following claims. a

What I claim is 1. In an airplane wing construction, in combination, a flap on the upper surface of the wing and slightly to the rear of the forward edge thereof, a trailing aileron adapted to operate in conjunction therewith and means including tog le jointed levers and a rod connecting said flap and aileron for raising them successively, adapted to increase the dra and decrease the lift on one side of the mac ine at low speed and large angles of attack on the main wing.

- 2. In an airplane wing construction, in combination, a flap on the upper surface of the wing and slightly to the rear of the forward edge thereof, a trailing aileron adapted to operate in conjunction therewith and means connecting said flap and aileron for operating them successively consisting of toggle jointed levers pivotally connected to sm flap and a portion of t e wing and a rod pivotally connected to said levers and to said aileron and adapted to increase the drag and decrease the lift on one side of the machine at low speed and high angles of attack on the main wing when the aileron is raised beyond a predetermined point.

3. In an airplane wing construction, in combination, a movable flap adapted normally to occupy a recess extending adjacent the forward edge of the wing, a trailing aileron rearwardly of said flap, connections between said flap and aileron involving a lost motion connection whereby said aileron can belowered without affecting the nose flap but will operate to raise the nose flap when said trailing aileron is raised a predetermined amount. a

4. In an airplane wing construction, in combination, a nose flap extending adjacent a portion of the forward edge of the wing and normall occupying a recess therein, means inclu ing toggle jointed levers and a rod for holding said fiap in retractive position, a trailing aileron rearwardly of said flap adapted to have a relative up and down movement from normal position and a lost motion connection between said aileron and nose fla whereby the nose flap is raised when said trailing aileron is raised a predetermined amount.

Signed at Washington, District of Columbia, this 2nd day of October, 1923.

CLEM H. CONGDON. 

